Uncomfortable feet are one potential issue. Walking becomes awkward and difficult, especially while wearing shoes, due to the thickness and misshaping of the infected nail as the fungus progresses.

Untreated toenail fungus can also cause athlete’s foot because it can migrate to the neighboring skin and create red, itchy, and cracked skin. The warm, moist environment found within shoes is ideal for the fungus to thrive in and spread.

The likelihood of a widespread infection is even more concerning as it offers a major risk, especially for those with weakened immune systems like those with diabetes. The fungus can enter the skin and cause cracks, which can lead to cellulitis, a bacterial skin illness that can be fatal. It is possible for the infection to enter the bloodstream and prove lethal if it is serious enough.